705 Data Processing System

In a September 1990 blockbuster announcement, IBM introduced System/390 -- the company's most comprehensive roll-out of products, features and functions in more than a quarter of a century. Encompassing a family of 18 new IBM Enterprise System/9000 processors (10 air-cooled models and eight water-cooled models), System/390 drew on such technologies as high-speed fiber optic channels with IBM's new ESCON architecture, ultra-dense circuits and circuit packaging for higher performance, integrated encryption/decryption for sensitive data, extended supercomputing capabilities, and twice the processor memory previously available.

System/390 processor

It was around that same time that some industry observers were declaring the impending death of the mainframe. One such analyst wrote in the March 1991 issue of InfoWorld, for example, "I predict that the last mainframe will be unplugged on March 15, 1996."

To be fair, the "mainframe," circa 1991, was a dead end. But IBM believed (along with a lot of its customers) that this way of computing -- serious, secure, industrial-strength -- would always be in demand. Hence, the System/390. With the 390, IBM stuck with "big iron" but reinvented it from the inside -- infusing it with an entirely new technology core, reducing its price, and building support for open standards and operating environments like Linux. That new technology was expressed by Complementary Metal Oxide Silcon (CMOS)-based processors, which used far less electricity, took up much less space and cost less than bipolar processors.

Those advantages and the other benefits of near-constant availability, ironclad security and massive computing power stimulated increased demand for IBM large-scale computers. After 1992, shipments of mainframe computing capacity have increased more than 30 percent annually. Indeed, that same InfoWorld pundit, who in 1991 predicted the death of the mainframe, wrote in February 2002: "It's clear that corporate customers still like to have centrally controlled, very predictable, reliable computing systems -- exactly the kind of systems that IBM specializes in." In other words, the king is dead ... long live the king.

One of the main drivers of mainframe acceptance and growth in recent years has been the proliferation in network computing and e-business users and applications. To help customers better harness the power of this pervasive medium, IBM unveiled in October 2000 the IBM eServer zSeries 900 (below), the first mainframe built from scratch with e-business as its primary function.

eServer zSeries 900

The reinvented mainframe was built to handle the unpredictable demands of e-business, allowing thousands of servers to operate within one box. The first in a new class of e-business servers, the z900, which works hand-in-hand with z/OS -- the z900's flagship operating system -- was designed for high speed connectivity to the network and to data storage systems, scalability in the face of unpredictable spikes in workload or traffic, and near zero downtime when clustered. In other words, the z900 allows customers to push performance and connectivity to the outer limits without any concessions to reliability and security. The ability to run thousands of virtual servers within one physical box makes the z900 the ideal platform for users with intensive e-business operations, such as application service providers, Internet service providers and technology hosting companies.

In May 2003, IBM rolled out the eServer zSeries 990 as the world's most sophisticated server. The result of an investment of more than $1 billion in four years, the z990 builds on the breakthrough technology of the z900 and sets a new standard for enterprise-class computing.

eServer zSeries 990

The z990 (above) is the most powerful and scalable IBM mainframe in the half-century history of that product. It features up to 9,000 MIPS (million instructions per second) on 32 processors -- double the processors and almost triple the system capacity of the z900; can handle 450 million e-business transactions a day (a clustered z990 can handle up to 13 billion transactions a day -- exceeding the average weekly volume on the New York Stock Exchange); provides up to 512 I/O channels, double the number of its predecessor; and offers four times the memory of the z900 (256GB compared to 64GB).

The heart of the z990 is the IBM multichip module (MCM) -- the densest, most advanced semiconductor and packaging technology in the world. The redesigned 3.7" x 3.7" x .75" module contains 16 chips mounted on 101 layers of ceramic glass connected to over 5,000 I/O pins by 500 meters of wire. The new MCM is 50 percent smaller, enabling the z990 to deliver almost three times the processor capacity of the z900 in the same footprint. The module uses IBM's leading-edge copper and Silicon-on-Insulator (SOI) technology and contains over 3.2 million transistors.

For the past 50 years, the mainframe has served as the backbone of large-scale computing. It has both adapted to new requirements and adopted and exploited new technology. It is being used today in ways that were literally unimaginable back in the era of the IBM 701. So to the extent that the past is prologue, it's probably fair to say that when it comes to the "mainframe" .... you ain't seen nothing yet.

For detailed information about and images of many of IBM's mainframes down through the years, visit our mainframe Mainframes reference room.